Strut bushings

[ray schrauwen]

U-cup Rod Seal - Source: theoringstore.com Part Number: 626-008-5747, Buna-N 70 shore U-cup

Note: requires a 5/16" counterbore. The seal is 0.065" thick, counterbore needs to be 0.060" to properly load the seal. That means the total depth on that drawing should be set to 0.160", 0.060 for the seal and 0.100" for the stop in the back. Very low friction with this type of seal. I don't have any water in my strut using it.

Perfect, thanks! My strut is bored to 5/16" already. I only need to move bearings around etc.

[CraigP]

That drawing shows a concept to try. I don't have a press fit plug currently in mine. I fabricated a small plate to go over the back of the strut and affixed it with two, 2mm hex head screws. There are 3 holes in the picture, I broke a tap in the lower hole, so it's not used. I was trying to come up with something that was less work. If you come up with another way, please share!

[ray schrauwen]

Ok. Not possible on my strut. I'll think about it a while.

Is that originally a 1/4" strut?

[CraigP]

No, it's a 3/16" strut...

[Hydrocarbon82]

Have you guys seen anyone who's modded the TFL stinger for a Speedmaster bushing? If i'm measuring correct, the lead teflon it uses is 0.25" OD. It appears I could replace them with a 0.25" OD brass tube and use this Speedmaster stinger bushing (link).

Otherwise I'm thinking of just getting the whole 3/16" Speedmaster stinger for $40. It's 0.2" longer but I can deal with that.

[zooma]

Have you guys seen anyone who's modded the TFL stinger for a Speedmaster bushing? If i'm measuring correct, the lead teflon it uses is 0.25" OD. It appears I could replace them with a 0.25" OD brass tube and use this Speedmaster stinger bushing (link).

Otherwise I'm thinking of just getting the whole 3/16" Speedmaster stinger for $40. It's 0.2" longer but I can deal with that.

I was getting ready to post the same question. Very interested in any solutions for inserting a Speedmaster floating bushing into the TFL stinger. I have three of these in use now.

[CraigP]

Yes, you can use the floating bushing in a strut with a 0.250" ID. You can bring the stuffing tube deep into the strut, or use a smaller, separate 1/4" OD tube to fully support the floating bushing. Teflon lined Bushings will not hold up with water intrusion, regardless of other statements made. I think many of us have experienced short life of the lead/teflon bushing, or in the least, the bushing in the back of the strut.

I'm currently using 3, lead/teflon bushings with 0.30" space in between them. It's working great for me, but I'm keeping the water out! So if you run an unsealed strut, then the floating bushing will hold up the best under the water/oil/grease lubrication of an unsealed strut.

Note: if your stinger has a loose fit to the 1/4" tubing, then use some Locktite Blue to hold it in place. If it spins, it will really wear out the aluminum housing.

[Hydrocarbon82]

The TFL stinger definitely isn't sealed, there's a good 1/4" gap at the front. I'll get a speedmaster bushing need time I order then use a separate 1/4" stub tube in the stinger. I plan to flair the front so it can't slide backwards.

[CraigP]

Why not just Locktite it in? The 1/4" tube isn't supposed to turn or move...

[zooma]

Yes, you can use the floating bushing in a strut with a 0.250" ID. You can bring the stuffing tube deep into the strut, or use a smaller, separate 1/4" OD tube to fully support the floating bushing. Teflon lined Bushings will not hold up with water intrusion, regardless of other statements made. I think many of us have experienced short life of the lead/teflon bushing, or in the least, the bushing in the back of the strut.

I'm currently using 3, lead/teflon bushings with 0.30" space in between them. It's working great for me, but I'm keeping the water out! So if you run an unsealed strut, then the floating bushing will hold up the best under the water/oil/grease lubrication of an unsealed strut.

Note: if your stinger has a loose fit to the 1/4" tubing, then use some Locktite Blue to hold it in place. If it spins, it will really wear out the aluminum housing.

So, wouldn't the TFL stinger bushings have to be machined to .25 inside dia?

[Hydrocarbon82]

The TFL lead bushings are 3/16" ID x 1/4" OD, so no. It could be 6mm because I can't measure it perfectly (flush & chamfered), but most TFL struts show 6.35mm ID on various sites.

[CraigP]

My comments were based on the ID being 0.250", so if it's metric, you'll have to machine a tube or machine the stinger, depending on the measurements. It's up to each modeler to consider the exact implement to use on your boat. Seems that making/modifying parts is a big part of the hobby!

[kfxguy]

Why not just Locktite it in? The 1/4" tube isn't supposed to turn or move...

If it can't move then you can't angle the strut unless you make the screw slot in the strut bigger.....so actually it is supposed to be able to move some.

[kfxguy]

The only potential problem I see with using the floating bushing in a title strut is the aluminum isn't as hard as the Speedmaster aluminum. It's almost like the Tfl one is made of pot metal while the Speedmaster is made from billet aluminum. So I'd imagine the Tfl would wear faster. I dunno. I guess I don't have a dog in this fight because I don't use bushings anyway. I've got a couple struts to machine for bearings, if anyone is interested I could take pics as I do it.

[CraigP]

If it can't move then you can't angle the strut unless you make the screw slot in the strut bigger.....so actually it is supposed to be able to move some.

I was talking about a second piece of tubing, not the stuffing tube. I have a stinger strut on my mono, it has a fixed, brass tube in there which sets and provides a bearing surface for the floating bushing. But that tube is in there good, you'd have to drill it out to get it out.